more trap behind corner trap ?

[dadumtish]

if I have bass traps ( 6 inch deep rock wool ) across the corners wall to ceiling ( 2 feet wide ) - leaving a gap behind.

would it be best to fill this gap in with more rock wool ?

will it make a difference ?

should it be dense or fluffy rock wool ?


I am still seeing some bass issues , as when i move away ffrom the sweet mix spot to the corner where the door is
the kick drum becomes much deeper and full of low end body

and I still do have a biggish null at 95 hertz or so at the mix area.

[Weasel9992]

Originally Posted by dadumtish

if I have bass traps ( 6 inch deep rock wool ) across the corners wall to ceiling ( 2 feet wide ) - leaving a gap behind.

would it be best to fill this gap in with more rock wool ?

will it make a difference ?

should it be dense or fluffy rock wool ?

It's always best if you can get all the way into the corners. Mineral wool would be fine...the denser stuff would be great, but if all you've got is the other stuff on hand it'll work too.

Originally Posted by dadumtish

I am still seeing some bass issues , as when i move away ffrom the sweet mix spot to the corner where the door is
the kick drum becomes much deeper and full of low end body

and I still do have a biggish null at 95 hertz or so at the mix area.

How did you treat your back wall? Have you done anything with the wall/ceiling corners?

Frank

[jwl]

Getting more material behind the traps in the corners will help, as Frank says. But it won't help a ton. You'd be better off putting that material elsewhere in the room, the rear wall, wall/ceiling corners, or possibly behind your front speakers on the front wall.

[Fab4ever]

Ok, now I'm confused. I thought it helps to have some air behind your bass traps... is that not true?

[Weasel9992]

Originally Posted by Fab4ever

Ok, now I'm confused. I thought it helps to have some air behind your bass traps... is that not true?

The corner filling design will work better down lower.

Certainly, if you don't have anything on the back wall or at your reflection points or anywhere else in the room, you should take care of that before filling the corners...that's true. But assuming that you do, and you're just wondering whether filling the corners will help, it will.

Frank

[Ethan Winer]

Originally Posted by Fab4ever

Ok, now I'm confused. I thought it helps to have some air behind your bass traps... is that not true?

The best absorber is absorbing material. When cost is a factor you can use half the material, and leave a gap, and that's almost as good as solid material. You'll fine a more detailed explanation here in the section Optimizing the air gap:

Acoustic Treatment and Design for Recording Studios and Listening Rooms

--Ethan

[Fab4ever]

Thanks Frank and Ethan. NOW I understand!

Not to hijack, but I'm planning on making bass traps from 4 inches of OC 705, with at least two and possibly four inches of air behind it, mounted in corners. Does that sound potentially effective in a small room?

[Ethan Winer]

Yes, that will be great.

[amd]

In order to tame bass in a small room, is it more effective to treat all corners including ceilings with 4 or 6 inches of 703 and leave an air gap behind or treat half of the corners (not ceilings) and fill them up entirely with 703?

[Ethan Winer]

Treat all the corners with an air gap. That will be about twice as good as having only half the corners filled fully.

--Ethan

[amd]

Originally Posted by Ethan Winer

Treat all the corners with an air gap. That will be about twice as good as having only half the corners filled fully.

--Ethan

Thank you Ethan!

[dadumtish]

Ok, things are working out well thanks to all your advice .
I put 6 inches wall to ceiling behind the other traps in the corners and dropped the speaker height ,
I have approx 12 inches thick of trapping in 3 corners now.
average levels are
70 db from 55 to 125 hertz
76 db from 125 to approx 200
81 db from 200 to 300 -
then
86db 300 to 500
82db 500 to 10 k+
I feel I need a sub woofer , as the mackie 624s only work down to about 50 hertz,
so do you think getting a sub will bring the range up to 125 hertz up enough ?
any thing I should watch if getting a sub ?

[Weasel9992]

Originally Posted by dadumtish

Ok, things are working out well thanks to all your advice .
I put 6 inches wall to ceiling behind the other traps in the corners and dropped the speaker height ,
I have approx 12 inches thick of trapping in 3 corners now.
average levels are
70 db from 55 to 125 hertz
76 db from 125 to approx 200
81 db from 200 to 300 -
then
86db 300 to 500
82db 500 to 10 k+
I feel I need a sub woofer , as the mackie 624s only work down to about 50 hertz,
so do you think getting a sub will bring the range up to 125 hertz up enough ?
any thing I should watch if getting a sub ?

Do you really *need* a sub? I mean, there's no too much out there with useful sub-50Hz information...bass, kick, some video FX, that sort of thing. If you're doing video post, gaming or maybe techno/R&B, then you may need one. If not, then you probably don't need one. If you don't need a sub, then I wouldn't bother with one. There are a bunch of things to think about when you add a sub: where to put it, tuning it with the mains (crossover point, balance), how it's going to mess with the low end room acoustics, etc. Each one of those issues will have to be dealt with...in the meantime you're making your job harder, not easier.

I'm not saying don't get a sub...I'm just suggesting that you think twice.

Frank

[Ethan Winer]

Originally Posted by dadumtish

I feel I need a sub woofer , as the mackie 624s only work down to about 50 hertz

I have Mackie 624s with a sub in my living room home theater system and it's great. But for stereo mixing you'll do better with full range speakers and no sub. Any chance you can trade up to a pair of Mackie 824s? The problem is a good sub will likely cost as much as the trade-up, and you'll still have the problem of integrating the sub.

--Ethan

[dadumtish]

I hate to say this ,
but I am an idiot . - a true idiot
I was using reaper to test the recordings and discovered that the reaper master channell does not behave
correctly ( maybe because i misconfigured it , im not sure ) so that nothing is output as it should .
if the single drum channell ( like the snare ) is soloed - it sounds great , but if you solo the actual reaper master channell,
it loses transients and volume .
I guess my ears were getting used to this choked sound
I noticed ordinary mp3s sounded great , but anything in reaper sounded out of phase and dull in the monitors and the phones
I am not knocking reaper - i just need to figure out what could be causing it - im sure i messed up a setting somewhere

I moved the files over to cubase and POW! the sound just came alive -
huge amounts of low bass and lovely snare and tom transients
it actually sounds pretty damn amazing and what i hear in the phones also matches the monitors

- i dont need a sub - far from it !
i just need to use my brains a bit more ;-)


but thanks for the great advice , your reponses confirmed that its my lack of experience thats causing me most problems.


on a second note - the mackie 624s come with enviroment switches for the low end ( normal , wall and corner ) - I have so much bass trapping around them - between them and the wall that i switched the settings to normal - and the lowend is now flat from 50 to 500 within + - 6 db - i measured it a few times to be sure

I actually cant wait to get home from work and start making some music